Pigmented ink-jet inks tend to have certain advantages over dye-based inks for ink-jet printing on conventional print media. Some of these advantages are light and ozone fastness of the printed image and good permanence on porous photo media. There are challenges associated with the use of pigmented ink-jet inks, however, such as insufficient gloss and lack of adequate scratch durability, especially on certain types of media such as porous photo paper. Prior efforts to improve gloss and durability of ink-jet printed images have generally involved coating the printed medium or adding polymeric binders to the inks. Although polymeric binders may enhance the gloss and durability characteristics of some inks, there is a limit to the amount of polymer that can be added to an ink before the viscosity of the liquid becomes too high for the ink to be reliably jetted from a thermal ink-jet pen. There is continuing interest in the development of pigmented ink-jet inks that have good gloss and scratch durability characteristics.